IMPROVED WATER REPELLENCY AND SURFACE DYEING OF POLYESTER FABRICS BY PLASMA TREATMENT

Polyester fabrics were successively extracted with benzene and water using the Soxhlet method and later dried under vacuum conditions. Then they were treated with O2 or CF4 plasma under different power, pressure and time conditions. Electron Spectroscopy for Chemical Analysis (ESCA) clearly indicated the development of surface oxidation and surface fluorination by plasma irradiation. Longer treatment times, higher power levels and lower pressure values created more significant surface modifications. Oxygen plasma treatment improved both the water uptake and surface dyeability while CF4 plasma resulted in excellent water repellency and unexpected improved surface dyeability. Intense fluorination reactions and simultaneous unsaturated bonds and trapped free radical formation may be responsible for the coexistence of these two contradictory behaviors. According to the SEM images of treated and untreated fabrics, oxygen plasma resulted in significant changes in the surface morphology while CF4 plasma created an even smoother surface structure than that of untreated fabrics. Aging analysis clearly showed insignificant post-plasma modifications under open laboratory conditions.